/* SBB Web Font Faces */
@font-face {
  font-family: "SBB";
  src: url("https://nk2028.shn.hk/yindian/fonts/SBBWeb_v1_9/SBBWeb-Thin.woff2") format("woff2");
  font-weight: 100;
  font-style: normal;
}

@font-face {
  font-family: "SBB";
  src: url("https://nk2028.shn.hk/yindian/fonts/SBBWeb_v1_9/SBBWeb-Light.woff2") format("woff2");
  font-weight: 300;
  font-style: normal;
}

@font-face {
  font-family: "SBB";
  src: url("https://nk2028.shn.hk/yindian/fonts/SBBWeb_v1_9/SBBWeb-Roman.woff2") format("woff2");
  font-weight: 400;
  font-style: normal;
}

@font-face {
  font-family: "SBB";
  src: url("https://nk2028.shn.hk/yindian/fonts/SBBWeb_v1_9/SBBWeb-Bold.woff2") format("woff2");
  font-weight: 700;
  font-style: normal;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --ice-white: #fafbfc;
  --snow: #ffffff;
  --frost: #f4f6f8;
  --birch: #e1ddd8;
  --stone: #5a6a7a;
  --pine: #1a2332;
  --charcoal: #0f1419;
  --shadow: rgba(26, 35, 50, 0.08);
  --accent: #4a7ba7;
  --accent-light: #6b9bc3;

  --font-sans: "SBB", "Helvetica Neue", Helvetica, Arial;
  --font-cjk-sans: "Source Han Sans HC", "Source Han Sans K", "Noto Sans CJK KR", "Source Han Sans SC", "Noto Sans CJK SC", "Source Han Sans", "Noto Sans CJK JP", "Source Han Sans TC", "Noto Sans CJK TC", "Noto Sans KR", "Noto Sans SC", "Noto Sans TC";
}

body {
  font-family: var(--font-sans), sans-serif, sans-serif;
  background: var(--ice-white);
  color: var(--snow);
  line-height: 1.7;
  min-height: 100vh;
  padding: 0;
}

:lang(zh-HK) {
  font-family: var(--font-sans), var(--font-cjk-sans), sans-serif, sans-serif;
  font-language-override: "KOR";
}

:lang(en-GB) {
  font-family: var(--font-sans), sans-serif, sans-serif;
}

.container {
  max-width: 1080px;
  margin: 0 auto;
  min-height: 100vh;
}

header {
  background: var(--snow);
  padding: 4rem 3rem 0 3rem;
  border-bottom: 1px solid var(--frost);
}

.lang-toggle {
  position: absolute;
  top: 3rem;
  right: 3rem;
  background: transparent;
  border: none;
  padding: 0.5rem 1rem;
  cursor: pointer;
  font-size: 0.9rem;
  color: var(--stone);
  transition: all 0.2s ease;
  font-weight: 400;
  letter-spacing: 0.02em;
}

.lang-toggle:hover {
  color: var(--charcoal);
  transform: translateY(-1px);
}

.lang-toggle::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--accent);
  transition: width 0.3s ease;
}

.lang-toggle:hover::after {
  width: 100%;
}

h1 {
  font-size: 3rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  margin-bottom: 0.25rem;
  color: var(--charcoal);
}

.subtitle {
  font-size: 1.5rem;
  color: var(--stone);
  font-weight: 300;
  letter-spacing: 0.03em;
}

main {
  padding: 4rem 3rem;
}

section {
  margin-bottom: 3rem;
}

h2 {
  font-size: 1.75rem;
  font-weight: 400;
  margin-bottom: 1.5rem;
  color: var(--charcoal);
  border-left: 2px solid var(--charcoal);
  padding-left: 1.25rem;
  letter-spacing: -0.01em;
}

p {
  margin-bottom: 1rem;
  color: var(--stone);
}

.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.25rem;
  margin-top: 2rem;
}

.tool-card {
  background: transparent;
  padding: 1.25rem;
  border: 1px solid var(--birch);
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  text-decoration: none;
  display: block;
  color: inherit;
  position: relative;
}

.tool-card::after {
  content: "→";
  position: absolute;
  right: 1.25rem;
  top: 50%;
  transform: translateY(-50%) translateX(-4px);
  opacity: 0;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  color: var(--stone);
  font-size: 1.1rem;
}

.tool-card:hover {
  border-color: var(--stone);
  background: var(--frost);
}

.tool-card:hover::after {
  opacity: 1;
  transform: translateY(-50%) translateX(0);
}

.tool-title {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--charcoal);
  margin-bottom: 0.4rem;
  letter-spacing: -0.005em;
  transition: color 0.2s ease;
}

.tool-card:hover .tool-title {
  color: var(--pine);
}

.tool-desc {
  font-size: 0.85rem;
  color: var(--stone);
  line-height: 1.5;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--charcoal);
}

.github-link {
  display: inline-block;
  background: transparent;
  color: var(--pine);
  padding: 0.75rem 1.5rem;
  margin-top: 1rem;
  border: 1px solid var(--birch);
  font-weight: 400;
  font-size: 0.95rem;
  letter-spacing: 0.01em;
}

.github-link span {
  position: relative;
}

.github-link:hover {
  color: var(--charcoal);
  border-color: var(--charcoal);
}

footer {
  background: var(--frost);
  padding: 2.5rem;
  text-align: center;
  color: var(--stone);
  font-size: 0.9rem;
  border-top: 1px solid var(--frost);
}

@media (max-width: 768px) {
  body {
    padding: 0;
  }

  header {
    padding: 3rem 1.5rem 2rem;
  }

  h1 {
    font-size: 2.25rem;
  }

  main {
    padding: 2.5rem 1.5rem;
  }

  .lang-toggle {
    top: 1.5rem;
    right: 1.5rem;
  }

  .tools-grid {
    grid-template-columns: 1fr;
  }

  h2 {
    font-size: 1.5rem;
  }
}